21366085 has 8 divisors (see below), whose sum is σ = 27611640. Its totient is φ = 15777984.

The previous prime is 21366077. The next prime is 21366091. The reversal of 21366085 is 58066312.

It can be written as a sum of positive squares in 4 ways, for example, as 872356 + 20493729 = 934^2 + 4527^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21366085 - 2³ = 21366077 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 164290 + ... + 164419.

It is an arithmetic number, because the mean of its divisors is an integer number (3451455).

Almost surely, 2^21366085 is an apocalyptic number.

It is an amenable number.

21366085 is a deficient number, since it is larger than the sum of its proper divisors (6245555).

21366085 is a wasteful number, since it uses less digits than its factorization.

21366085 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 328727.

The product of its (nonzero) digits is 8640, while the sum is 31.

The square root of 21366085 is about 4622.3462656967. The cubic root of 21366085 is about 277.4863667788.

The spelling of 21366085 in words is "twenty-one million, three hundred sixty-six thousand, eighty-five".